<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>sidebar</title>
</head>
<body>
  <h1>this is sidebar iframe</h1>
  <script src="http://libs.baidu.com/jquery/1.4.2/jquery.min.js"></script>
  <script type="text/javascript">
    var bg = ['#ff0000','#00ff00','#0000ff'];
    var rand = parseInt(Math.random()*3);
    $('body').css('background', bg[rand]);
  </script>
</body>
</html>
